exclude some code from the qmake build

Change-Id: Ic989a2cc5106496a2c5f13c863a0a87d5cd2d963
Reviewed-by: Joerg Bornemann <joerg.bornemann@nokia.com>
Reviewed-by: Marius Storm-Olsen <marius.storm-olsen@nokia.com>

src/corelib/global/qlibraryinfo.cpp

@@ -148,6 +148,8 @@ QSettings *QLibraryInfoPrivate::findConfiguration()
     \sa QSysInfo, {Using qt.conf}
 */
 
+#ifndef QT_BUILD_QMAKE
+
 /*! \internal
 
    You cannot create a QLibraryInfo, instead only the static functions are available to query
@@ -210,6 +212,8 @@ QLibraryInfo::isDebugBuild()
     return false;
 }
 
+#endif // QT_BUILD_QMAKE
+
 static const struct {
     char key[14], value[13];
 } qtConfEntries[] = {